I'm not keen on live action. I feel that once you take it out of animation and put it in the real world you have to start comparing it to the real world. Suddenly you start to notice its flaws and pit falls and you can no longer suspend your disbelief. I'm trying to imagine Aria as a live action and I'm hating the idea.

That said, there probably are anime that would translate well to live action.

Cross Game. Considering Adachi's track record, it actually stands a fairly decent chance... his style tends to suit the everyday life situations of most Japanese drama series.

While I would love to see Rurouni Kenshin, Skip Beat! or ARIA as a live-action drama, I think they would be pretty difficult to film. (Because of special kenjutsu techniques, grudge devils and Lory's costumes, and Martian landscapes and lifeforms, respectively)

So for the more realistic ones with a chance of success, I'd go for Ouran High School Host Club, Hajime no Ippo, and maybe True Tears, Spiral or Clannad.